You could treat this as an opportunity. Record yourself with one of those small, handy electronic voice recorders. Critique your ennunciation. Try to improve it. Being aware of faults in your speech may make you self-conscious about speaking and thus urge you to silence. If your speech becomes excellent it may lead to a career in acting or doing voice-overs. "If you lose, you win If you win, you win."

I do this when I reading through a concept I don't straight away understand, I read it aloud, whether it be mathematical or literary.
It helps me understand what it is I'm reading, I consider it a learning technique, so it doesn't bother me.